This blog follows and explains the processes behind interesting geological events. The emphasis is on those events that are energetic, explosive, and have led to, or have the potential to lead to, disasters.

Welcome!

This blog provides commentary on interesting geological events occurring around the world in the context of my own work. This work is, broadly, geological fluid dynamics. The events that I highlight here are those that resonate with my professional life and ideas, and my goal is to interpret them in the context of ideas I've developed in my research. The blog does not represent any particular research agenda. It is written on a personal basis and does not seek to represent the University of Illinois, where I am a professor of geology and physics. Enjoy Geology in Motion! I would be glad to be alerted to geologic events of interest to post here! I hope that this blog can provide current event materials that will make geology come alive.

Tuesday, September 24, 2013

Pakistan earthquake and its new island

A magnitude 7.7-7.8 earthquake hit Pakistan today with an epicenter at about 15 km depth. It was well inside the borders of Pakistan and far from the ocean. Although only a few dozen (46) casualties have been reported as I write this (10:00 p.m. Central Time), the location of the quake is remote and it is likely that casualties will rise, with some estimates being in the thousands (WAPMERR, The World Agency of Planetary Monitoring and Earthquake Risk Reduction). As this unfolds, an intriguing observation with speculations has hit the news--a mysterious island has risen from the ocean. It is reported to be 20-40 feet high and about 100 feet wide and lies about 350 feet out in the sea from the Gwadar coast (these numbers are very tentative--one report says that it's a mile out to sea, which seems more consistent with the picture that I've included above). It appears to be several hundred miles from the epicenter.
Residents of Gwadar have reported that an earthquake in 1968 produced an island that remained for about a year before vanishing (but it's reported also to have occurred in the 1940's so I don't know if this is an inconsistency in historical reporting or if it has happened more than once). What could have caused this mysterious phenomenon? Speculation at the moment is our old culprit, liquefaction--the sudden transformation of wet, but solid, sediments to a weak mush upon shaking, just like jiggling quicksand turns it to a mush (for more on liquefaction and the general phenomena discussed here, see my book "The Dynamics of Disaster" to be released by Norton Press on October 21!!). When this happens, structures such as buildings can sink into the ground because it can no longer support their weight. The liquified material can also squirt up through cracks in the ground forming sand- or mud-volcanoes, and the speculation here is that the island is a big mud volcano.
This area of the Arabian Sea is known for its mud volcanoes.* Here the oceanic crust of the Arabian Sea is being subducted under Eurasia at a rate of about 4 cm/year. A sediment pile has been building up on top of this subduction region to a thickness exceeding 6 km, a pile of wet gooey muck. The coastal region is known for mud volcanoes on land, and for the episodic formation of islands of them in the shallow waters off the coast. These are typically destroyed within months. Here's a seismic reflection image of a buried mud volcano from the reference * listed below:

Sometimes these mud islands appear in places that others have appeared before. One, called Malan island, appeared in 1999, unaccompanied by any noticeable earthquake, reoccupying a site of one that had been formed in 1945. It appears to have been driven by methane of bacterial origin.

One of the largest reported mud volcanoes is a complex 100-m high. It has been hanging around since at least 1840 and appears not to have changed much in the intervening decades. Methane of bacterial origin is persistently discharged into its crater mud lake. Eruptions of these gases often show periodicities of several hours that may be related to ocean tides. I'm not sure how the dating is done, but the article * below says that the presence of mud volcano activity in this region can be demonstrated for the last 460,000 years.

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==>My book:The Dynamics of Disaster <==

Published by W.W. Norton--Click on image to go to Amazon.com

Synopsis of Book and Reviews

If you want to learn a bit of the science behind earthquakes, landslides, volcanic eruptions, tsunamis, rogue waves, cyclones and hurricanes, and tornadoes, this is an introduction that weaves together stories of various disasters--some barely known to much of the world--their causes and dynamics, and some suggested actions we can take to protect ourselves. The book is available both in paper and as an audio CD.

"This is a fantastic book. I've recommended to colleagues at FEMA and am using it as a text for my disaster classes. It really demonstrates how knowledge of the environment should inform policy. It was a page turner for me!"--Dr. Trish on Customer Reviews at Amazon.com

''Geologist Kieffer argues that we don't understand disasters as well as we should. She contrasts 'stealth disasters' caused by long-term human impact, including climate change and soil erosion, with natural disasters or 'acts of God,' which are also increasingly affected by human actions . . . [A] highly accessible look at disasters.'' --Booklist

"Kieffer's brisk and lucid presentation has some of the relish with which surgeons reputedly regale each other with tales from the operating theatre. Laid out before the reader are the suppurating wounds, scalds, tremors, and scars acquired by the Earth over millennia, centuries, decades, or minutes."--Claudio Vita-Finzi in The Times of London

"If you are an amateur weather geek, disaster wonk or budding student of the earth sciences, you will want to read this book. (If you're squeamish, skip the chapter titled "A Plague of Snakes.")--Seattle Times by Mary Ann Gwinn

"[T]he clarity of Kieffer’s writing, coupled with her careful choice of supporting graphics, makes the content engaging and accessible to a wide readership." Alison Stokes in TheTimesHigherEducation

“In The Dynamics of Disaster, famed geoscientist Susan Kieffer merges stories and science in a fascinating introduction to the dangerous side of the Earth, with key insights for citizens and enough excitement to captivate the full range of students.”—Richard B. Alley, author of Earth: The Operator’s Manual

"Both general readers and working scientists will enjoy this well-written book--and learn some things they did not know...Summing up: Highly recommended. Lower-division undergraduates through professionals; general audiences."--by Seth Stein in Choice Reviews Online (of the American Library Association), April 2014

"This [impressive] book ought to be placed in the hands of politicians, engineers, insurance assessors and, frankly, anyone who sees sense in understanding the processes and systems that guide our planet." --Geographical, December 2013, by Jonathan Wright

This book is part of a recent trend--one that is just beginning, but is likely to grow--in which scientists, especially young ones, seek to move beyond the "disasters are bad" view presented in beginner classes to a more sophisticated and nuanced view…Seth Stein in Physics World (U.K.)

"It is like a "Magic School Bus" outing for adults, with Kieffer acting as Ms. Frizzle, guiding the reader around the world to disaster hotspots, where she analyzes and breaks down the physical characteristics that contribute to events in those areas."--Summit Daily, December 20, 2013

#1 in list of Best Sellers: Geology, from May 2013 to March 2014. LibraryJournal.com

Victoria Raschke's Reviews (Jan. 09, 2019) Kieffer's explanations of the how natural disasters occur is perfectly suited to the interested layperson. The section on rogue waves was worth the price of admission in that it explains something that always seemed kind of supernatural. If you have any interest at all in understanding our living planet and why it sometimes feels like it would be happy to be rid of us, this is the book for you.